add navigator demo for Android and single activity multi fragment

demo/index.ts

@@ -10,4 +10,5 @@ export default [
     'src/ModalDemo',
     'src/NetworkDemo',
     'src/StorageDemo',
+    'src/NavigatorDemo',
 ]

demo/src/NavigatorDemo.ts

@@ -0,0 +1,50 @@
+import { Panel, scroller, vlayout, text, layoutConfig, LayoutSpec, Color, gravity, IVLayout, Group, IText, navigator } from "doric";
+import { colors, label } from "./utils";
+@Entry
+class NaivgatorDemo extends Panel {
+    build(root: Group) {
+        scroller(vlayout([
+            text({
+                text: "Navigator Demo",
+                layoutConfig: layoutConfig().w(LayoutSpec.AT_MOST),
+                textSize: 30,
+                textColor: Color.WHITE,
+                bgColor: colors[1],
+                textAlignment: gravity().center(),
+                height: 50,
+            }),
+            ...['Counter', 'EffectsDemo', 'ImageDemo', 'LayoutDemo',
+                'ListDemo', 'ModalDemo', 'NavigatorDemo',
+                'NetworkDemo', 'ScrollerDemo', 'SliderDemo', 'Snake', 'StorageDemo'].map(e =>
+                    label(e).apply({
+                        height: 50,
+                        bgColor: colors[0],
+                        textSize: 30,
+                        textColor: Color.WHITE,
+                        layoutConfig: layoutConfig().exactly().w(LayoutSpec.AT_MOST),
+                        onClick: () => {
+                            navigator(context).push(`assets://demo/${e}.js`, `${e}.js`)
+                        },
+                    } as IText)
+                ),
+            label('POP').apply({
+                width: 200,
+                height: 50,
+                bgColor: colors[0],
+                textSize: 30,
+                textColor: Color.WHITE,
+                layoutConfig: layoutConfig().exactly(),
+                onClick: () => {
+                    navigator(context).pop()
+                },
+            } as IText),
+        ]).apply({
+            layoutConfig: layoutConfig().atmost().h(LayoutSpec.WRAP_CONTENT),
+            gravity: gravity().center(),
+            space: 10,
+        } as IVLayout)).apply({
+            layoutConfig: layoutConfig().atmost(),
+        }).in(root)
+    }
+
+}